Wire rolling system and method



L. S. BLAIR WIRE ROLLING SYSTEM AND METHOD Filed May 22. 1961 Oct. 27, 1964 United States Patent O 3,153,954 WIRE ROLLING SYSTEM AND METHOD Lloyd S. Blair, Williamstown, Mass, assignor to General Electric Company, a corporation of New York Filed May 22, 1961, Ser. No. 111,830 4 Claims. (Cl. 80-35) This invention relates to metal rolling equipment and processes capable of producing rod or wire of various sizes in one continuous operation without requiring shutdown of the equipment for adjustment.

Processing of rod or wire is usually accomplished by one of three methods: extruding, rolling or drawing. This invention relates to the rolling method of forming wire; but since wire rolling equipment is well known in the art, the virtues of the rolling methods over those of extruding and drawing will not be pointed out. Although the rolling method of producing rod or wire offers a considerable number of advantages over the others, one big disadvantage to the rolling method, as well as the other methods, is that after forming wire of a particular size or cross-sectional area, it is necessary to shut-down the equipment and make adjustments or introduce additional equipment into the production line so that a different size of wire can be formed. These adjusting operations, of course, result in a great loss of time in which expensive equipment is not being utilized and a great loss of manhours in making the adjustments. The present invention eliminates the adjusting step once the equipment has been started and consequently is able to produce a greater amount of rod or wire of different sizes in a given time and at a reduced cost.

Accordingly, it is an object of the invention to provide a wire rolling system capable of producing wire or rod of a variety of shapes and sizes in one continuous sequence.

It is another object of the invention to provide an integrated tandem rod mill system for rolling metal stock to predetermined wire or rod size and shape in a programmed automatic sequence.

A further object of the invention is to provide an improved method for making different sizes or shapes of wire from a continuous strand of metal stock of substantially uniform cross section with a minimum of lost time when changing from one size or shape to another.

Briefiy stated, one aspect of the invention relates to a tandem rod mill system for rolling metal stock to predetermined wire size and shape having a series of pairs of grooved rollers. The rollers are arranged so that each pair between which the stock passes has mating grooves of a cross-sectional area or size larger than the grooves of the following pair of rollers, when considered in the direction which the metal stock is moved. Opening and closing means are provided to independently open any of the pairs of rollers to a position in which the rollers are inoperative for shaping the metal stock or to independently close any of the pairs of rollers to a position in which the rollers are operative. Also, a control means is provided to schedule the actuation of the opening and closing means in any order so long as all pairs of rollers from the entering pair to the last emergent pair are closed for any given size or shape of rod or wire to be rolled. This enables lengths of rod lee P or wire of predetermined different sizes to be formed in a predetermined order. Another aspect of the invention is a method for producing different sizes or shapes of wire from a continuous strand of substantially uniform cross section in which the opening and closing of the rollers is programmed so that the final cross section of the strand is determined by the last pair of rollers through which it passes.

Further objects, features and advantages of the invention will become apparent from the following specification, claims, and drawings in which:

FIG. 1 shows a schematic perspective view of a tandem rolling mill'and associated equipment embodying the invention;

FIG. 2 shows a cross-sectional view on an enlarged scale of a pair of rollers of one mill stand from FIG. 1.

Referring now to the drawings, FIG. 1 shows an integrated tandem rod mill system comprising an unreeler 1, a straightener 2, a plurality of roll mill stands generally shown at 3, an annealer 4, a recoiler 5, and a programming means 6. A substantially uniform strand of metal stock 7 to be formed into wire or rod of predetermined cross-section is normally received on a reel; and consequently, the first step of an integrated rolling system is to place the reel in the un-reeler 1 before feeding through straightener 2, which removes any kinks or bends in the stock. The stock 7 is then fed through the series of roll mill stands 3, numbered from 10 through 13 and shown in tandem relationship in the drawing. It is to be understood that the number of stands 3 employed may be greater or less than the number illustrated in the drawing, depending on the extent to which the stock is to be reduced. For example, approximately 18 stands would be needed to reduce generally square electrical grade copper stock to generally rectangular .100" x .100" wire.

Each of the stands 3 is provided with a pair of grooved rollers, similar to those designated 15 and 16 in stand 13, between which the stock passes to be reduced to the desired size or cross-sectional shape. The grooves in successive pairs of mating rollers are aligned in the direction the stock travels. Although the rollers are shown as having parallel axes, those skilled in the art will realize that in some applications, alternate pairs of rollers may be at right angles. The cross-sectional area of the openings defined by the mating grooves in suc cessive mill rollers are of different predetermined fixed sizes, and the stands 3 are arranged so that the stock passes through the grooves in the order of larger to smaller. That is, each pair of rollers between which the stock passes has mating grooves with a cross-sectional area larger than the grooves of the following pair of rollers when considered in the direction in which the metal stock is moved, which is from left to right in the drawing. In other words, the roller grooves in stand 10 are larger than those of stand 11, which are in turn larger than stand 12, etc. 1

Since tandem roll mills per se are known in the art, a detailed description of the structure will not be given. The mill stands can be provided with a common drive shaft throughout the length of the integrated unit and a fixed ratio taken from this drive shaft through to the rollers, thus enabling the mill stands to be grouped. Alternatively, each individual mill stand can be provided with its own source of power. Each pair of rollers from the entering end of the mill runs faster than the preceding pair. This difference in speed between each pair of rollers is equal to the percentage of reduction in the metal stock caused by each pair of rollers. 'The percentage of reduction which can be obtained per stand is dependent upon such variables as the shape of the groove and the hardness of the material being rolled.

Each of the stands 3 is provided with opening and clos ing means such as indicated at 19 for stand 13, to independently open any of the pairs of rollers toa position in which the'rollers are inoperative for shaping the metal stock or to independently close any of the pairs of rollers to an operative position. The opening and closing means 19 may be any suitable means capable of separating or closing the rollers of a particular pair, such as a motor and gearing arrangement.

After the metal stock has passed through the last roll mill stand, it is passed through the annealer 4 and then wound into another coil by the recoiled 5. Suitable shearing devices (not illustrated) for cutting the wire when a reel is completed or when the size is changed may be added adjacent the annealer 4.

The remaining component of the invention is control means, generally shown as automated programming means 6, for scheduling the actuation-of the" opening and closing means for each stand 3. An example of such programming means is shown as a tape reader 20 a master control 21. Since automated programming devices are known in the art, a detail explanation will not be made. The provision of programming means 6 enables the wire forming process to be a continuous strand operation. 1

An overall description of how the system operates can be given by considering a particular run of the system when wire or rod of several diflerent sizes needs to be produced. The information pertaining to the size and length of wire required will be coded and placed on a tape 22. All of the rollers of the various mill stands 3 are first adjusted and moved into operative position. When the system is started, tape 22 is fed to tapereader 20 which transmits the information to master control 21, which in turn starts the rolling operation. Since all of the rollers are operative for shaping the metal stock, the size of the first wire produced is the smallest which the system can provide with the given groove sizes. After the required length of wire having a predetermined small size has been produced, the master control 21 automatically actuates the opening means of one or more pairs of rollers having grooves of the smaller sizes so that such rollers are opened to an inoperative position. The remaining pairs of rollers continue to operate to thereby form wire of the next desired larger predetermined size. For example, after a length of smallest diameter wire has been produced, the opening means 19 of stand 13 could be actuated so that rollers 15 and 16 would beino'perative and the next length of wire formed would be of the size determined by the size of the roller grooves in stand 12. Or, the opening means for a plurality of stands such as 13 and 12 could be actuated so that the next lcngthof wire formed would be of the size of the roller grooves in stand 11. In etfect, the programming means 6 schedules the actuation of the opening means to determine the last or emergent pair of rollers through which the wires passes.

This procedure may be automatically continued as determined by the programming means to form wire of predetermined cross-sectional sizes in the order of smaller .to larger. The wire is then heat treated in the annealer 4 to remove internal stresses produced as it is shaped in the rollers, and finally coiled on the recoiler 5.

It will be appreciated that the number of difl'erent sizes or shapes of rod or wire which can be produced from a given system is theoretically only limited by the number of mill stands incorporated into the system. Also, it should be understood 'that'difierent sizes of wire can be formed in the order opposite to that described in the preceding paragraphs by closing the pairs of rollers in the opposite order, i.e. from larger groove size to smaller, so long as the programming means 6 instructs, in accordance with the invention, that all roll stands from the entering pair of rollers to the last or emergent pair are closed for any given size or shape of rod to be rolled.

Referring now to FIG. 2, a pair of rollers 23 and 24 of a typical mill stand 3 are shown having a plurality of mating grooves 25 and 26; 27 and 28; and 29 and 30. These grooves are shown as having a semi-circular cross-section, but it is to be understood that the grooves can be of shapes other than circular, if required. Generally, only one pair of grooves in each pair of rollers are utilized at one time and theradditional grooves can be used as spares in the event the grooves in operation become worn after repeated use. However, the additional grooves may be used to simultaneously form additional strands of wire by mounting several rolls of stock 7 on the un-reeler 1 and passing them simultaneously through the system in parallel.

It will be obvious to those skilled in the art that various changes and modifications may be made without departing from the invention. For example, means such asrolls fortaking up slack in the strand 7 may be provided, if needed, or means can be provided for coating the wire before it is wound on the recoiler 5, Accordingly it is intended in the appended claims to cover all such changes and modifications as fall within the true spirit and scope of the invention.

What I claim as new and desire to secure by Letters Patent of the United States is:

1. A tandem rod 'rnill system for rolling metal stock to predetermined wire size and shape comprising :a series of pairs of grooved rollers arranged so that each pair of rollers between which said stock passes has mating grooves of a predetermined fixed cross-sectional area larger than the grooves of the following pair of rollers when con sidered in the direction which said metal stock is moved,

opening and closing means to open independently any of said pairs of rollers to a position in which the pair of rollers is inoperative for shaping said metal stock and to close independently any of said pairs of rollers to a position in which the pair of rollers is operative for shaping said metal stock, and control means to schedule the actua tion of said opening and closing means to open or close one or more of said pairs of rollers in a predetermined order in which all pairs of rollers from the entering pair to the emergent pair needed to produce a given size and shape of wire are closed. 7

2. A tandem rod mill system for rolling metal stock to predetermined wire size and shape comprising: a series of pairs of grooved rollers arranged so that eachpair of rollers between which said stock passes has mating grooves of a predetermined fixed cross-sectional area largerthan the grooves of the following pair of rollers when considered in the direction which said metal stock is moved, opening means to open independently any of said pairs of rollers to a position in which said rollers are inoperative for shaping said metal stock, and programming means to schedule the actuation of said open ing means to open one or more of, said pairs of rollers having the smaller grooves before the remainderof said pairs of rollers having the larger grooves to thereby form wire of predetermined sizes in the order of smaller to larger. l

3. A tandem rod mill system for rolling metal stock to predetermined wire size and shape comprising: a series of pairs of grooved rollers arranged so that each pair of rollers between which said stock passes has mating grooves of a predetermined fixed cross-sectional area larger than the grooves of the following pair of rollers when considered in the direction which said metal stock is moved, closing means to close independently any of said pairs of rollers to a position in which said rollers are operative for shaping said metal stock, and programming means to schedule the actuation of said closing means to close one or more of said pairs of rollers having the larger grooves before the remainder of said pairs of rollers having the smaller grooves to thereby form Wire of predetermined sizes in the order of larger to smalier.

4. The method for producing difierent s zes or shares of Wire from a continuous strand of metal stock having a substantially uniform cross section comprising: passing the strand through a series of pairs of rollers having mating grooves arranged so that the cross section of predetermined fiXed ogening defined by the respective pairs of mating grooves decrease in size in the direction in which said strand travels, and controlling the opening and closing of said rollers so that the final cross section of said strand is determined by the last pair of rollers through Which it passes, whereby minimum time is lost in changing from one Wire size or shape to another.

References Cited in the file of this patent UNITED STATES PATENTS 290,002 Dodge Dec. 11, 1883 529,036 Lenox Nov. 13, 1894 838,781 Forsberg Dec. 18, 1906 2,679,680 Hanks June 1, 1954 3,081,653 Kincaid Mar. 19, 1963 OTHER REFERENCES Control Engineering, January 1960, pages 126130. Digital Computer Runs Hot Plate Mill. Copy in Patent Office Library. 

3. A TANDEM ROD MILL SYSTEM FOR ROLLING METAL STOCK TO PREDETERMINED WIRE SIZE AND SHAPE COMPRISING: A SERIES OF PAIRS OF GROOVED ROLLERS ARRANGED SO THAT EACH PAIR OF ROLLERS BETWEEN WHICH SAID STOCK PASSES HAS MATING GROOVES OF A PREDETERMINED FIXED CROSS-SECTIONAL AREA LARGER THAN THE GROOVES OF THE FOLLOWING PAIR OF ROLLERS WHEN CONSIDERED IN THE DIRECTION WHICH SAID METAL STOCK IS MOVED, CLOSING MEANS TO CLOSE INDEPENDENTLY ANY OF SAID PAIRS OF ROLLERS TO A POSITION IN WHICH SAID ROLLERS ARE OPERATIVE FOR SHAPING SAID METAL STOCK, AND PROGRAMMING 